Conservation and New Sources Yield Sustainable Water Supply

In drought-stricken New Mexico, Albuquerque’s aquifer levels are rising while customer demand is dropping.
Conservation and New Sources Yield Sustainable Water Supply
Allen Maestas (left) and Zack Layne set up their acoustic listening equipment to check for leaks in Albuquerque’s water system.

Rainfall patterns are changing around the globe. The southwestern U.S. has suffered from an extended drought, on and off, for decades. In 2011, parts of this region experienced conditions approaching those of the 1930s Dust Bowl. Water levels were dropping in many lakes, reservoirs and aquifers. But in Albuquerque, the situation was already well under control.

The Albuquerque Bernalillo County Water Utility Authority (ABCWUA) is a state-level regional organization tasked with providing water to the City of Albuquerque. They confronted the water supply problem head-on in the early 1990s, and since 2008, aquifer levels have risen as much as 50 feet in some areas. How they accomplished this, despite the drought, is a lesson in creative problem-solving, innovation and conservation.

ABCWUA is currently delivering the same volume of water they did in 1985, but they’re serving an additional 250,000 people. And their models predict the aquifer will continue rising for at least another 20 years, despite projected growth of the Albuquerque metro and suburban population.

“Long-range planning began back in the ‘60s,” notes Katherine Yuhas, water conservation officer for ABCWUA. “That’s when we decided to tap into our Colorado River Basin entitlement and started building a pipeline to the San Juan River.”

Groundwater woes

The Middle Rio Grande Aquifer has been Albuquerque’s primary source of potable water since settlements were first established in the early 18th century. The aquifer was originally thought to be “virtually limitless,” but problems began to appear in the 1960s.

“Early assumptions were that any water pumped from the aquifer would be recharged by the river,” Yuhas explains. “It turns out that wasn’t quite correct.

“There’s definitely a connection, but the transfer of water from the river to the aquifer wasn’t nearly as fast as we thought. There’s a significant latency, and that’s when we realized we needed to look at other sourcing options.”

The Rio Grande River runs through the area, but its flow varies greatly from year to year. Sometimes it’s reduced to a mere trickle, and only some of that flow can be used since Texas also holds Rio Grande water rights. By the time the river crosses the Mexican border, if at all, it can hardly be called “grand.”

The Upper Colorado River Basin Compact of 1948 specifies allotments for all the surrounding states. New Mexico’s entitlement is 11.25 percent. That equates to 0.84 million acre-feet annually. Of course, the total flow from the basin has been dropping during this extended drought, but New Mexico has continued to extract their fair share. That water was not easy to tap, however, since it’s west of the Continental Divide and almost 200 miles from Albuquerque.

First efforts

The earliest effort focused on tapping that share of the Colorado River allotment. In the 1960s, a pipeline from the San Juan River was built for this purpose. Albuquerque city leaders contracted for 48,200 acre-feet annually. This water had to be moved over the Continental Divide, requiring diversion points in the San Juan drainage basin, 26 miles of tunnels, four inline reservoirs and a pumping station.

Ultimately, that water is delivered directly into the Rio Grande. From there it flows to the Albuquerque water uptake station. Originally, that water was used for non-potable applications like agriculture, endangered species flows and compensation for groundwater pumping. Dissolved and suspended particulates were extremely high, as is typical for rivers in the Southwest.

“That resulted in less demand on the aquifer, but Albuquerque was still in a growth boom, so we knew we needed to do more,” Yuhas says. “Studies in the 1980s showed that continued pumping from the aquifer would result in land subsidence, so we started pushing for water conservation, and for extraction of potable water from the river.”

Planning for extracting that water began in the mid-1990s. Water conservation efforts had already halted the drop in aquifer levels, but the rise in aquifer levels began in 2008 when the San Juan – Chama Drinking Water Project came online. A $160 million advanced treatment plant was built to process hard water from the Rio Grande into a potable state. It has been averaging 58 mgd, with a capacity of 80 mgd (see sidebar).

Output is delivered directly into the distribution system and currently supplies close to 90 percent of the city’s demand. Since 2008, groundwater pumping has decreased and aquifer levels continue to rise.

Educational outreach

ABCWUA also began an outreach program to educate citizens about the need to conserve water. Programs for schools, HOAs, developers and individual homeowners are all part of the mix.

“Many of our current customers were in grade four when they took our water conservation classes. So they grew up knowing what they need to do in terms of reducing waste,” Yuhas says. “Compliance has, in general, been exceptional.”

The usual billboards, media spots and leaflets with water bills are in regular use. Beyond that, classes for grade schools, including field trips, are provided at no cost. The students love the experience and take home some good lessons. Teachers have access to a wealth of educational materials on the ABCWUA website, which has been an effective resource.

ABCWUA also hires students from the University of New Mexico, located in Albuquerque, as seasonal workers. UNM has degree programs in several water-related professions, and students can get hands-on training at ABCWUA facilities. Like most water utilities, the need for new recruits is paramount as older staff retires.
Classes for homeowners are also offered, with credits on their water bills awarded for successful completion. Courses in xeriscaping, mulching, in-home conservation, fruit and vegetable gardening, and rainwater recycling are popular and well attended.

Data shows that customers who attend the water conservation classes reduce their water use by an average of 18 percent. This has been a significant factor in ABCWUA’s success with their water conservation efforts.

Restaurant managers have a lesson to learn as well. A city ordinance now requires waiters to omit the previously obligatory glass of water for patrons, unless specifically asked for. Here again, compliance has been exceptional. “If there is a complaint filed, I call the manager in an attempt to fix that problem,” Yuhas says.
ABCWUA will also send field techs to provide free assessments of home water use and conduct leak checks at no cost. They use acoustic leak detection equipment and have enjoyed a high success rate, uncovering everything from faulty toilet valves to underground pipe breaks.

Rebate program

ABCWUA runs a rebate program that also reaps huge benefits — for customers and for the authority. Built into the ABCWUA budget, this program awards on average $1 million each year to qualifying applicants. Rebates are available for:

  • Replacement of lawns with xeriscaping
  • Low-flow showerheads
  • Low water-use appliances (washers and toilets)
  • Application of mulch to reduce evaporation
  • Rainwater catchment systems
  • Tree care to reduce water use for irrigation and provide shade (tree-bates)
  • Evaporative cooler thermostats
  • Hot-water recirculation systems (so the wait for hot water is shorter)

“Pretty much anything you could think of that saves water will be covered under our rebate program,” says Yuhas. “Rebate amounts vary by category, but whatever the customer installs, they will be rewarded based on the amount of water saved.”

The xeriscaping program has been particularly successful. Since implementation, it has eliminated 8,465 grass lawns and a total area of 11,263,000 square feet of otherwise water-hungry foliage. Of note, 38 percent of delivered potable water is still used for the irrigation of lawns and landscaping foliage.

Some of the most significant gains have been seen on commercial properties, where landscaping choices have a greater impact. For new construction, turf is limited to no more than 30 percent of the total development.

The use of mulch on commercial developments is also heavily promoted as a means to reduce landscape water evaporation. ABCWUA provides that mulch at a reasonable cost. It’s a mixture of 50 percent animal stable bedding (mostly straw), 30 percent biosolids from their wastewater treatment plant, and 20 percent shredded green waste.  

Cost for this mulch is $25/ton ($10/cubic yard). Customers can pick it up at their Compost del Rio Grande facility, where staff will load their trailer or truck for no extra charge.

Violations and penalties

Although compliance with water restrictions and usage guidelines has been good, ABCWUA receives an average of 1,000 citizen water-waste complaints each year. These are usually minor items, like sprinkler systems activating at incorrect times and water flowing from a customer property into a public right of way. The process for submitting complaints is simple and can be done online anonymously.

Complaints are handled with a visual inspection, if needed, but are followed up with a series of notifications and penalties for noncompliance. The protocol is:

  • Two warning notices sent by mail
  • First noncompliance penalty is $20
  • Subsequent penalties escalate to $50/$100/$2,000
  • Service termination

“It rarely goes beyond the $20 penalty,” Yuhas says. “That’s almost always the wake-up call that triggers compliance. We have assessed some $2,000 penalties, but those are usually on commercial operations or apartment complexes.”

A new program called “Water by the Numbers” limits water use based on the day of the week and season. Compliance is voluntary, and it encourages customers to ramp up their watering slowly during spring and back down again in the fall.

During severe drought conditions, their drought management program kicks in. At that point “Water by the Numbers” does indeed become mandatory. Also, commercial operations face additional restrictions on water use proportional to their demand.

Distribution details

The water distribution system has some old pipes. A quarter of them are over 50 years old. Made of steel, many of them are rusted and have been leaking precious water. The system has some 92 miles of these pipes, 34 percent of which have been categorized as “high risk.” As of fiscal 2015, 15 miles of these pipes have been replaced with PVC. Work orders related to failing pipes have already decreased by 25 percent.

ABCWUA is on a continued maintenance schedule, replacing those old pipes at a rate of 2 miles per year. At that rate, however, the entire system wouldn’t be upgraded until 2054.

“We’re expecting to ramp up that replacement schedule,” says Anthony Montoya, chief engineer for the ABCWUA Water Resources, Planning & Engineering Division. “With upcoming rate increases dedicated to old pipe replacement, we expect to finish that work much sooner.”

Those old pipes are being fitted with advanced metering infrastructure monitors at key locations to detect leaks. Monitors are also used on commercial operations, providing real-time data on water use and helping diagnose problems.

In addition, field technicians are using mobile leak-detection equipment to do regular inspections of the rest of the distribution system. The current schedule inspects 87 percent of the smaller-diameter distribution lines every three years.

As in most jurisdictions, developers must foot the cost for water infrastructure in their subdivisions. The usual permitting, approval and inspection process is handled by the City of Albuquerque. ABCWUA works with the city, consulting as needed.

Education is key

Albuquerque’s average per-capita water use has dropped from 250 gpd in 1995 to 134 in 2014, largely due to the authority’s successful conservation efforts. Total production has also dropped — from 40 to 32 billion gallons over that same period.

Yuhas says there are many contributing factors in the success, not the least of which are public and government support.

“The key factor, in my opinion, has been educating the citizens about how to respond to the drought. Telling them they have to do something is one thing, but having them know why it has to be done is the key. And I think we’ve done that quite well.”


The San Juan – Chama Drinking Water Project

The Albuquerque Bernalillo County Water Utility Authority (ABCWUA) has been delivering water from the Colorado River Drainage Basin to the Rio Grande Basin since the early 1970s. Water from the Rio Grande was processed with simple filtering and delivered to the system as non-potable for commercial and farming applications.

Potable water had been drawn from the Middle Rio Grande Aquifer since the city was established in the early 18th century. This convenient arrangement was disrupted in the 1990s when ABCWUA realized the aquifer wasn’t as “limitless” as they had previously assumed. The aquifer level was falling as a result of demand exceeding recharge by a factor of two. And there were real concerns about land subsidence.

“That’s when we decided we needed to look for other sources of potable water,” says Katherine Yuhas, water conservation officer for ABCWUA. “The most direct solution was an advanced water treatment plant that could handle the raw water delivered from the Rio Grande.”

That decision was the genesis of the San Juan – Chama Drinking Water Project, which ran from 2004 to 2008. The $400 million project was funded by a series of seven dedicated rate increases over a period of several years.

The biggest chunk of money — $160 million — was spent on a new advanced water treatment plant, capable of processing the hard water of the Rio Grande into potable water. Capacity is 80 mgd, and it has been averaging about 72 percent of that since 2008 when it first went online.

An additional $240 million went toward other infrastructure, including:

  • A raw water pumping station on the Rio Grande, built to resemble a typical Spanish mission church and blend in aesthetically.
  • An adjustable diversion dam and intake structure, with fish screens and passages installed to reduce the environmental impact on local species, one of which (the Rio Grande silvery minnow) is on the endangered list.
  • Eight miles of pipe to connect the pumping station to the treatment plant.
  • Thirty-eight miles of distribution pipelines, some running under the Rio Grande.

Output feeds directly into the Albuquerque distribution lines. In 2009, it delivered 7 billion gallons, about 21 percent of total consumption. Currently, it provides close to 90 percent of demand. Further, this water contains virtually no arsenic, unlike water from the aquifer. By blending that water with groundwater still being pumped, the new federal guidelines on arsenic content have been met well ahead of schedule.

Given the highly variable flow of the Rio Grande, output occasionally exceeds demand. In that happy scenario, excess output is diverted to a deep well to help recharge the aquifer. Aquifer levels have been rising, and that is expected to continue for at least another 20 years based on models for population growth.

Less water is being pumped from the aquifer, but the bulk of the recharge comes from snow melt in the mountains to the north. Yuhas notes that “with the reduction in demand from our water conservation program, we can now think of the aquifer as a ‘bank account’ that we can tap, should the drought continue or worsen.”



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